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* Crazy 2
 #846105  
  shinenrise - 12/06/17 12:35
 
  A healthy 22-year-old man who weighs 70 kg (154.3 lb) volunteers for a phase I clinical trial investigating the properties of a newly developed antimicrobial agenl The drug ls found to have a volume of distribution of 10 L and exhibits first-order elimination kinetics. The rate of drug clearance is calculated to be 7 L/hr. It is determined that repeating the second dose when 75% of the drug is eliminated will minimize toxicity while maintaining trough levels above the minimum inhibitory concentration. Based on these research findings, which of the following is the most appropriate dosing interval for this drug?

A. 1 hour
B. 1.5 hours
C. 2 hours
D. 2.5 hours
E. 3 hours
 
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* Re:Crazy 2
#3354492
  anasteps - 12/06/17 19:34
 
  Do maintain dose formula
They asking for MD
 
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* Re:Crazy 2
#3354495
  sawtooth - 12/06/17 19:37
 
  C i think  
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* Re:Crazy 2
#3354499
  roshank06 - 12/06/17 21:11
 
  Yup its C. Took me awhile to get. 75 cleared would be two half lives. Half life is 1 hr from this drug. Great questions. Thank you!  
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* Re:Crazy 2
#3354508
  shinenrise - 12/07/17 01:48
 
  t1/2 = Vd x 0.7/ Cl

plug into this formula i.e 10x 0.7/7= 7/7= 1.

now to eliminate 75% of drug , 2 half life are needed therefore, 2hr.

so C is the correct answer.
 
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* Re:Crazy 2
#3354529
  halux - 12/07/17 08:59
 
  2hrs as 75% occurs at 2nd t 1/2

:)
 
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